In U.S. Pat. No. 3,135,057, a flight simulator is disclosed utilizing a sphere assembly mounted on a pedestal which has an air bearing for supporting the sphere. Three motor and race assemblies are located within the sphere which are able to impart rotary movement to the shell in three planes corresponding to roll, pitch and yaw. The center of gravity of the shell coincides with its geometric center. A projection screen on the inner surface of the sphere provides a pilot with a visual impression of flight as the dome moves in response to control signals.
Such a simulator, while possibly adequate at one time for simulating flight conditions would allow too much lag between control measures taken and the simulated response to adequately represent flight in a modern aircraft. Similarly, the sphere cannot achieve the high G maneuvers called for in simulating emergency type conditions, a major advantage of flight training in a simulator.
In U.S. Pat. No. 4,514,347, a static dome simulator is disclosed which has a layer of synthetic material bonded to a domed shaped geodetic structure, the geodetic structure providing sufficient strength to provide "a free standing structure." In such a structure, the observed visual scene responds in a manner which simulates corresponding movement of an actual aircraft. However, while visual changes occur, the pilot does not get the actual feel of an aircraft changing under him nor feel how the changes in control response affect the center of gravity of the aircraft. Consequently, a static base simulator may not accurately represent flight conditions.
While motion base simulators using domes are known, such domes are typically produced of aluminum. FIG. 1 shows an aluminum skin motion base simulator. A dome 1 is mounted on a platform 2 supported by actuators 3 which impart movement to the dome to simulate YAW, pitch and roll maneuvers. The dome 1 has a plurality of panels 4 which mate at flanges 5. Juncture flanges 6 are located at the flange intersections. Typically, the panels are bolted together and the junctures are riveted. A superstructure 7 composed of interlocking trusses is used to stiffen the structure. As simulation technology has progressed, these domes have been subjected to higher G forces and stresses that, through repetitive dynamic loading on the flanges and junctures, can exceed the capabilities of the materials used, typically resulting in juncture failures and cracking. This necessitates dampening the action of the actuator system to prevent dome damage. This limits the simulator's ability to accurately duplicate normal aircraft and emergency manuevers. Also, such damage to the dome detracts from the projected image.